diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | sysdeps/x86_64/_mcount.S | 55 |
2 files changed, 48 insertions, 13 deletions
diff --git a/ChangeLog b/ChangeLog index a31f95a80d..24c2b65cb0 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2016-03-03 Paul Pluzhnikov <ppluzhnikov@google.com> + + [BZ #19490] + * sysdeps/x86_64/_mcount.S (_mcount): Add unwind descriptor. + (__fentry__): Likewise + 2016-03-03 H.J. Lu <hongjiu.lu@intel.com> * gmon/Makefile (noprof): Add $(sysdep_noprof). diff --git a/sysdeps/x86_64/_mcount.S b/sysdeps/x86_64/_mcount.S index ba13643464..a506d21dcd 100644 --- a/sysdeps/x86_64/_mcount.S +++ b/sysdeps/x86_64/_mcount.S @@ -24,19 +24,24 @@ #include <sysdep.h> - .globl C_SYMBOL_NAME(_mcount) - .type C_SYMBOL_NAME(_mcount), @function - .align ALIGNARG(4) -C_LABEL(_mcount) +ENTRY(_mcount) /* Allocate space for 7 registers. */ subq $56,%rsp + cfi_adjust_cfa_offset (56) movq %rax,(%rsp) + cfi_rel_offset (rax, 0) movq %rcx,8(%rsp) + cfi_rel_offset (rcx, 8) movq %rdx,16(%rsp) + cfi_rel_offset (rdx, 16) movq %rsi,24(%rsp) + cfi_rel_offset (rsi, 24) movq %rdi,32(%rsp) + cfi_rel_offset (rdi, 32) movq %r8,40(%rsp) + cfi_rel_offset (r8, 40) movq %r9,48(%rsp) + cfi_rel_offset (r9, 48) /* Setup parameter for __mcount_internal. */ /* selfpc is the return address on the stack. */ @@ -47,33 +52,50 @@ C_LABEL(_mcount) /* Pop the saved registers. Please note that `mcount' has no return value. */ movq 48(%rsp),%r9 + cfi_restore (r9) movq 40(%rsp),%r8 + cfi_restore (r8) movq 32(%rsp),%rdi + cfi_restore (rdi) movq 24(%rsp),%rsi + cfi_restore (rsi) movq 16(%rsp),%rdx + cfi_restore (rdx) movq 8(%rsp),%rcx + cfi_restore (rcx) movq (%rsp),%rax + cfi_restore (rax) addq $56,%rsp + cfi_adjust_cfa_offset (-56) ret - - ASM_SIZE_DIRECTIVE(C_SYMBOL_NAME(_mcount)) +END(_mcount) #undef mcount weak_alias (_mcount, mcount) - .globl C_SYMBOL_NAME(__fentry__) - .type C_SYMBOL_NAME(__fentry__), @function - .align ALIGNARG(4) -C_LABEL(__fentry__) - /* Allocate space for 7 registers. */ +/* __fentry__ is different from _mcount in that it is called before + function prolog. This means (among other things) that it has non-standard + stack alignment on entry: (%RSP & 0xF) == 0. */ + +ENTRY(__fentry__) + /* Allocate space for 7 registers + (+8 bytes for proper stack alignment). */ subq $64,%rsp + cfi_adjust_cfa_offset (64) movq %rax,(%rsp) + cfi_rel_offset (rax, 0) movq %rcx,8(%rsp) + cfi_rel_offset (rcx, 8) movq %rdx,16(%rsp) + cfi_rel_offset (rdx, 16) movq %rsi,24(%rsp) + cfi_rel_offset (rsi, 24) movq %rdi,32(%rsp) + cfi_rel_offset (rdi, 32) movq %r8,40(%rsp) + cfi_rel_offset (r8, 40) movq %r9,48(%rsp) + cfi_rel_offset (r9, 48) /* Setup parameter for __mcount_internal. */ /* selfpc is the return address on the stack. */ @@ -84,13 +106,20 @@ C_LABEL(__fentry__) /* Pop the saved registers. Please note that `__fentry__' has no return value. */ movq 48(%rsp),%r9 + cfi_restore (r9) movq 40(%rsp),%r8 + cfi_restore (r8) movq 32(%rsp),%rdi + cfi_restore (rdi) movq 24(%rsp),%rsi + cfi_restore (rsi) movq 16(%rsp),%rdx + cfi_restore (rdx) movq 8(%rsp),%rcx + cfi_restore (rcx) movq (%rsp),%rax + cfi_restore (rax) addq $64,%rsp + cfi_adjust_cfa_offset (-64) ret - - ASM_SIZE_DIRECTIVE(C_SYMBOL_NAME(__fentry__)) +END(__fentry__) |